There was an FBI presence Thursday morning at three homes in Everett, Massachusetts, but there's no threat to public safety, according to the agency's Boston field office.
A spokesperson for FBI Boston confirms the agency conducted court-authorized activity in the city, but did not share further information.
At least four people were arrested, witnesses told NBC10 Boston.
One man living in a building on Bradford Street said police knocked on his door while he was still in bed.
About a mile away, the same thing was taking place at a three-family home on Francis Street. Officers carried long guns while others carried boxes of evidence out of the building. A woman who lives inside says her 22-year-old son was arrested, although she wasn't sure why.
Neighbors said all the commotion was unexpected.
"I'm kind of used to a little dangerous neighborhood, but I am surprised it happened on my street," one woman said.
A third raid took place at an apartment building on Ferry Street, only steps from the Everett Police Department, which helped federal authorities with both law enforcement agencies describing the raids as authorized court activity.
"There's briefings that take place in order to have a coordinated response," said security analyst Todd McGhee. "They just don't go out like cowboys, that would not be best practices."
McGhee says the involvement of local law enforcement in FBI raids is critical.
"It's important that the local authorities really support the efforts of the federal authorities on these types of investigations," he said.
The U.S. Attorney's Office in Massachusetts has not responded to a request for more details about the raids and the reasons behind them.